This protocol will examine whether men are similar to or different from women in an acute alcohol administration study. Women are tested at two hormonally distinct phases of their menstrual cycle. Specifically, the study is testing 1) whether the subjective stimulant response to alcohol is different in males compared to females, and 2) whether the pharmacokinetic (PK) and pharmacodynamic (PD) responses to alcohol are different in women at the early follicular phase compared to the periovulatory phase of their menstrual cycle. Evidence suggests that estradiol and alcohol may share cellular localization with endogenous opioids. Estrogen has been shown in vitro models to facilitate the release of dopamine through direct actions on the receptor (Becker et al behavioral responses to stimulant drugs, which also act via the dopamine system. Hypotheses: 1. Women versus men: Women will have lower subjective stimulation response as measured on the Biphasic Alcohol Effect Scale (BAES) at the same blood alcohol levels compared to men. 2. Women at the periovulatory phase vs the early follicular phase: a. Women will have greater stimulation response as measured on the Biphasic Alcohol Effect Scale (BAES) to alcohol in the periovulatory phase, when levels of estradiol are expected to be higher, compared to the early follicular phase, based upon in vitro data showing that estradiol facilitates dopamine release, enhances stimulant responses to drugs in animals and binds with beta-endorphin to the same CNS cells possibly influencing the endogenous opiod stystem. b. Women will have similar elimination times and areas under the curve (AUCs) for alcohol metabolism in the two phases.